1. Field of the Invention
The present invention relates to a developer container which is used in electrophotograph image forming apparatuses, such as laser beam printers, copying apparatuses or the like.
2. Related Background Art
When an image forming apparatus, which employs electrophotographs, is used for a long time, the apparatus requires the exchange of a photosensitive drum and the replenishment or exchange of a developer as well as the adjustment, cleaning or exchange of other members (charging device and cleaning device). Maintenance of these process means was difficult for those other than servicemen that have special knowledge.
Then, in order to solve the inconvenience described above, there has been developed a process cartridge consisting of image forming means, such as a photosensitive drum, a developing device, and a cleaning device which are integrated with one another as a cartridge.
Thereby, this process cartridge allows a user to easily carry out this maintenance and exchange by himself when the process means requires maintenance, thereby making it possible to obtain high quality images a low cost.
Such a process cartridge comprises an agitating member, for example, as a developer agitator in a vessel of a developer which is a developer container, and the agitating member is driven from the outside of a toner container by transmitting a driving force by way of a gear or the like.
A run-through hole is formed at a wall of the developer container to transmit the driving force to the agitating member, and a driving-force transmitting member passes through the hole and the agitating member in the vessel is coupled with the gear outside the container by way of the driving force transmitting member. Therefore, it is feared that the run-through hole may allow the developer to leak outside. Then, for prevention of leakage of the toner, it is conventional to dispose a seal member having a lip portion, which is in contact with an entire circumferential surface of a shaft of the driving force transmitting member.
However, there has been a desire for further improvement of a seal member.